1. Field of the Invention
With reference to the classification of art as established in the United States Patent and Trademark Office the present invention is found in the general Class entitled, "Measuring and Testing" (Class 73) and more particularly in the subclass entitled, "volume or rate of flow-pitot tube" (subclass 212).
2. Description of the Prior Art
Water skis are well known and the popularity of the sport has made their use quite extensive. Many examples of these skis may be found in the general Class 9 and the subclass 310. However, in this classification of art, and insofar as is known, there has been no attempt to provide skis with a speed indicating device.
Water skis are well known and their popularity has increased to the extent that several hundred thousand are in use and waterskiing has become a popular participant sport. In order to perform acrobatic stunts or athletic exercises successfully on the skis it is often necessary to ascertain how fast one is travelling. If the boat providing the tow has no speed indicator this is a guess. In order to provide a speed indicating device there is carried in the present skis a pitot-type tube indicator device. A portion of this pitot-type tube is preferably carried in a downwardly extending rib. This rib is either a single rib or one of a dual rib configuration. These ribs increase the control of the ski and also allow the tube to be contained therein. The end of this tube is open to the flow of water. Insofar as is known, speed indicating devices generally applied to watercraft and the like have been propeller-type devices which extend below or outwards from the hull of the craft. Since water-skiing often times requires the person to slide onto shore or off ramps and the like, protrusions containing speed indicating apparatus obviously would not be satisfactory and also would be potential hazards to swimmers and the like.
In the present invention the indicating scale portion of the gauge device is placed on the forward and top of the ski. This gauge is operatively connected to pitot-type tube apparatus and is open on the rear side or extreme rear of a depending rib of the ski. This rib may be a single rib or one of a twin rib construction to be hereinafter more fully described. The indicating device may be a pivoted, needle-type indicator moved by pressure differential developed in the tube against a bias force provided in the gauge or it may be a water column gauge into a closed end tube. The pitot-type tube rear end is open to the water flow and has a diaphragm closure by which means the fluid in the pitot-type tube is maintained during the time that the ski is removed from the water. The means for removably retaining a diaphragm at the end of the tube are shown in the following embodiments, to be hereinafter more fully described, but many other means or methods of retaining or removably retaining a diaphragm closure of the pitot-type tube may be provided.